Distributed process framework

ABSTRACT

Providing a distributed processing framework. Initially, the process begins by building a server process plug-in by invoking a code generation module to generate required boilerplate and cross-platform code. Then commencing a server process by loading plug-in code and giving it a thread of control. In addition, client machines discovering the existence of a plug-in code being executed. Further, one or more client applications running on a client server at least issuing commands to the plug-in code, monitoring the events of the plug-in code, update the properties of the plug-in code without information regarding the plug-in interface.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/587,303 filed on May 4, 2017, which is a continuation of U.S.application Ser. No. 14/788,738, filed on Jun. 30, 2015 and bearing thesame title, which application claims the benefit of the filing date ofthe following United States Provisional applications for patent, both ofwhich are incorporated herein in their entireties: U.S. Provisional Ser.No. 62/019,270 filed on Jun. 30, 2014 and, U.S. Provisional Ser. No.62/019,330 filed on Jun. 30, 2014. Each of these applications isincorporated herein by reference in their entirety, including each ofthe Exhibits therein.

BACKGROUND

Traditionally, there is a significant amount of development costs andtime in the deployment of both real-time and non-real time distributedcomputing systems. Not only is this inefficient from a marketperspective but it also results in retarding significant technologicalgrowth as in many situations, products on the market tend to raise thetechnological floor and foster creativity to once again move beyondstatus quo. Thus, there is a need in the art for a system and method tosignificantly reduce the development costs and time to market associatedwith the production and deployment of both real-time and non-real-timedistributed computing systems.

SUMMARY

The SES Distributed Process Framework (SES-DP™) was designed tosignificantly reduce the development costs and time to market associatedwith the production and deployment of both real-time and non-real-timedistributed computing systems. The SES-DP Framework utilizes aclient-server model of distributed computing in which server machinesprovide hard-real-time or non-real-time computing services to clientmachines. The server side computing services, referred to as serverprocesses, are implemented as stand-alone server plug-ins that can beloaded and instantiated into a remote server at run time. Once loaded,each server process exports a process specific command and controlinterface that can be discovered and invoked by any client side machine.The SES-DP tool suite provides for the rapid development of both serverplug-ins and client applications. Server plug-ins are quicklyconstructed using the SES-DP code generator, which automatically takescare of cross-platform build details so that a server process can bewritten once and deployed across an assortment of server operatingsystems and hardware architectures. Client applications are quicklyconstructed using the SES-DP support for popular high-level scriptinglanguages, like Perl and Python. The SES-DP client-server networkprotocol provides additional support for rapid construction. Theprotocol has a simple, uniform design featuring extensible commandmessages that make it easy to add new server commands or change existingones. The developers of SES-DP have leveraged their extensivebackgrounds in distributed hard-real-time development to produce anefficient system that they use on a daily basis to build large-scaleclient-server systems. The SES-DP infrastructure has a proven trackrecord as a foundation for reliable distributed systems built at lowcost on accelerated schedules.

The following exhibits contain further information pertaining to thisdisclosure and they are incorporated into this application by the aboveincorporation by reference of the priority provisional applicationslisted above in the CROSS-REFERENCE TO RELATED APPLICATIONS section:

EXHIBIT A—CODE HEADER

EXHIBIT B—DEVELOPER'S GUIDE

EXHIBIT C—DEVELOPER'S GUIDE (UPDATED)

EXHIBIT D—DISTRIBUTED PROCESSING FRAMEWORK

EXHIBIT E—SES PRESENTATION

EXHIBIT F—SES-DP PRESENTATION

EXHIBIT G—SES CODE

BRIEF SUMMARY OF THE DRAWINGS

FIG. 1 is a block diagram showing a platform onto which embodiments andaspects of the disclosed embodiments may be incorporated or implemented.

FIG. 2 is a functional block diagram illustrating various componentsthat may be included in various embodiments.

FIG. 3 illustrates a command and event interface.

FIG. 4 is a flow diagram illustrating steps involved in an exemplaryembodiment.

FIG. 5 is a state diagram illustrating SES distributed process statetransitions.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

FIG. 1 is a functional block diagram of the components of an exemplaryembodiment of system or sub-system operating as a controller orprocessor 100 that could be used in various embodiments of thedisclosure for controlling aspects of the various embodiments. It willbe appreciated that not all of the components illustrated in FIG. 1 arerequired in all embodiments of the activity monitor but, each of thecomponents are presented and described in conjunction with FIG. 1 toprovide a complete and overall understanding of the components. Thecontroller can include a general computing platform 100 illustrated asincluding a processor/memory device 102/104 that may be integrated witheach other or, communicatively connected over a bus or similar interface106. The processor 102 can be a variety of processor types includingmicroprocessors, micro-controllers, programmable arrays, custom IC'setc. and may also include single or multiple processors with or withoutaccelerators or the like. The memory element of 104 may include avariety of structures, including but not limited to RAM, ROM, magneticmedia, optical media, bubble memory, FLASH memory, EPROM, EEPROM, etc.The processor 102, or other components in the controller may alsoprovide components such as a real-time clock, analog to digitalconvertors, digital to analog convertors, etc. The processor 102 alsointerfaces to a variety of elements including a control interface 112, adisplay adapter 108, an audio adapter 110, and network/device interface114. The control interface 112 provides an interface to externalcontrols, such as sensors, actuators, drawing heads, nozzles,cartridges, pressure actuators, leading mechanism, drums, step motors, akeyboard, a mouse, a pin pad, an audio activated device, as well as avariety of the many other available input and output devices or, anothercomputer or processing device or the like. The display adapter 108 canbe used to drive a variety of alert elements 116, such as displaydevices including an LED display, LCD display, one or more LEDs or otherdisplay devices. The audio adapter 110 interfaces to and drives anotheralert element 118, such as a speaker or speaker system, buzzer, bell,etc. The network/interface 114 may interface to a network 120 which maybe any type of network including, but not limited to the Internet, aglobal network, a wide area network, a local area network, a wirednetwork, a wireless network or any other network type including hybrids.Through the network 120, or even directly, the controller 100 caninterface to other devices or computing platforms such as one or moreservers 122 and/or third party systems 124. A battery or power sourceprovides power for the controller 100.

The SES Distributed Process Framework (SES-DP™) was designed tosignificantly reduce the development costs and time to market associatedwith the production and deployment of both real-time and non-real-timedistributed computing systems. The SES-DP Framework utilizes aclient-server model of distributed computing in which server machinesprovide hard-real-time or non-real-time computing services to clientmachines. The server side computing services, referred to as serverprocesses, are implemented as stand-alone server plug-ins that can beloaded and instantiated into a remote server at run time. Once loaded,each server process exports a process specific command and controlinterface that can be discovered and invoked by any client side machine.The SES-DP tool suite provides for the rapid development of both serverplug-ins and client applications. Server plug-ins are quicklyconstructed using the SES-DP code generator, which automatically takescare of cross-platform build details so that a server process can bewritten once and deployed across an assortment of server operatingsystems and hardware architectures. Client applications are quicklyconstructed using the SES-DP support for popular high-level scriptinglanguages, like Perl and Python. The SES-DP client-server networkprotocol provides additional support for rapid construction. Theprotocol has a simple, uniform design featuring extensible commandmessages that make it easy to add new server commands or change existingones. The developers of SES-DP have leveraged their extensivebackgrounds in distributed hard-real-time development to produce anefficient system that they use on a daily basis to build large-scaleclient-server systems. The SES-DP infrastructure has a proven trackrecord as a foundation for reliable distributed systems built at lowcost on accelerated schedules.

Various embodiments will be described using the term “SES DistributedProcess or SES-DP™. The SES-DP framework provides a generalized platformfor commanding and controlling user specific real-time or non-real-timeprocesses across multiple machines, processors, and processor cores. TheSES-DP™ infrastructure consists of one or more client machine(s) thatcommand and control a collection of realtime or non-real timedistributed process server nodes. Each SES-DP™ server node can becommanded to load, execute, and control one or more user specificprocessing tasks. Once active, user specific processing tasks can run inlock step with hardware based system clock plug-ins and communicate withother distributed processing tasks using the SES-DP™ publish/subscribeor stream I/O communication facilities.

Users utilize the SES-DP™ C++ code generation tools to produce userspecific processing plug-ins from a schema based XML description filethat specifies all of the commands, properties, events, streams, andpublish subscribe interfaces that the user process will require. Theuser specific processing plug-ins can then be pushed onto one or moreSES-DP server nodes and executed in hard-real-time or non-real timedepending on which operating system the selected SES-DP™ server orservers are running. Once running, the user specific distributed processcommand set can be remotely discovered and executed by any of the SES-DPnetworked client interfaces without client side code modifications orrecompilation. This allows new or updated user process code to beplugged into an operational system without bringing the system or any ofits active processes down.

The SES-DP™ framework provides powerful Perl based client side interfacemodules that allow users to load, command, and control all of theiravailable distributed processing plug-ins across multiple machines thatcould be running different operating systems from Perl. This allowsusers to configure and control large complex real-time distributedsystems or entire facilities from a single Perl script. User distributedprocess objects can be rapidly developed for any application includingreal-time dynamic hardware control systems, sequential process controlsystems, distributed real-time or non-real-time simulation systems, etc.

The SES-DP server, illustrated in FIG. 2, utilizes a collection ofbuilt-in subsystems that allow the server to handle a vast array of userspecific operations. These subsystems include the Multi-Client Commandand Control Server 202, the Event Manager 204, the System Root Process206, the Process Load Manager 208, the Hardware Resource Manager 210,the I/O Stream Manager 212, the Publish/Subscribe Manger 214, and theTime I/F Manager 216.

The SES-DP server 200 utilizes an advanced event notification interfacethat allows client applications to register listeners for server sideevents and receive and react to those server side events without pollingoperations. Client scripts and applications may register listeners forany of the SES-DP server specific or user distributed process specificevents that are resident within the server 200. If server side event istriggered and that event has one or more registered client listeners,the Multi-Client Command and Control Server 202 will notify theregistered clients by automatically transmitting the triggered event'sproperty list to those clients. Client applications leverage theSES_RtLib event object hierarchy to register object oriented client sidecallbacks when a server side event is fired.

The Multi-Client Command and Control Server 200 is responsible forhandling all external network based client connections to the SES-DPserver node 200. This interface provides full support for multipleclients and handles all command and control traffic directed toward boththe SES-DP System Root Process 206 and the instantiated user distributedprocess objects. In addition, this interface automatically handles theSES-DP server side event notification transmissions to all registeredclients.

The System Root Process 206 handles the command and controlresponsibilities for each of the subsystem managers that are containedwithin the SES-DP server 200. These include the Process Loader Manager208, the Hardware Resource Manager 210, the I/O Stream Manager 212, thePublish/Subscribe Manager 214, and the Time I/F Manager 216. Inaddition, the System Root Process 206 handles the configuration of theSES-DP message logger subsystem 218 as well as all server statereporting operations. The System Root Process 206 accomplishes this byexporting a command and control interface that is utilized in theconfiguration and control of each of the attached subsystem managers. Asis the case with all SES-DP framework exported command interfaces, theserver command and control interface is automatically discovered by allclients that connect to the server. For a complete description of theavailable system root command set, refer to section x.x.

The Process Load Manager 208 is responsible for loading, initializing,and running user distributed process objects on the SES-DP server 200.It is also responsible for unloading the user distributed processobjects when they are no longer desired and handling any exceptions thatoccur during process instantiation. User distributed process objectplugin modules must first be loaded into the SES-DP distributed processplug-in repository before they can be instantiated within the SES-DPserver 200. This is typically handled using the resident FTP server 220on the system. The Process Load Manager 208 is controlled through theSES-DP System Root Process 206 using the process load exported commandset. When loading a distributed process, users must specify the plug-inDLL or shared object name along with the instance number to assign thedistributed process object once it is instantiated. The SES-DP system200 allows multiple instances of the same user distributed process to beinstantiated as long as each process has a unique instance number andthe server configured maximum process specific number of instances hasnot been exceeded. If either of these restrictions is not adhered to, anexception is thrown and the new process is not instantiated. Because theSES-DP framework utilizes an OS abstraction layer, all SES-DP code is OSindependent and users do not have to rewrite their distributed processcode when they want to run their code on a SES-DP server that isutilizing a different operating system. Once a user has completed his orher distributed process code, he or she can then cross compile this codefor any of the SES-DP supported operating systems. This is accomplishedusing the OS specific project file or makefile that is auto generated bythe SES-DP distributed process code generator 230(1)-230(n) when theuser code was generated. The auto generated project files and makefilesutilize a canonical OS specific sub-directory naming convention thatallows all target flavors of the user distributed process object toexist below the same directory tree. The SES-DP distributed processplug-in repository tree contains plug-in sub-directories that utilize OSspecific target names such as pemw32, pemets, pclinux, safaris gee, etc.This scheme is utilized throughout the SES-DP framework and can be foundin both the SES-DP SDK and the SES-DP server nodes. When an OS specificbuild is performed on the user distributed process codebase, the targetplug-in binary file is automatically transferred into the appropriate OSspecific directory on the development workstation. The OS specificbinary plug-in modules can then be transferred into the appropriate OSspecific directory on an available SES-DP server using the SES-DPframework provided distributed process FTP transfer scripts.

The Hardware Resource Manager 210 is responsible for allocating hardwareresources to the loaded distributed process objects. Once a systemhardware resource has been allocated to a specific distributed process,that resource can be utilized within both the distributed processspecific real-time processing method and any of the exported distributedprocess command methods. Supported hardware resources include: Analog IOcards 240, Digital IO cards 242, system bus controller cards 244, NICcards 246, RS-422 cards, custom FPGA based boards 248, etc. In additionto allocating the hardware resources, the Hardware Resource Manager 210ensures that multiple user distributed process objects do not attempt tore-task programmable hardware in incompatible ways. A typical example ofthis would occur if a newly instantiated distributed processing objectwas allowed to reprogram an FPGA device that is already programmed witha different FPGA design and under the control of a separate distributedprocess. If allowed, this condition would most likely result in a systemcrash. The SES-DP Server Hardware Resource Manager 210 prevents thiserror condition by only allowing one active resident design to existwithin any of its FPGA devices at a time.

The SES-DP framework provides two powerful mechanisms that allowmultiple process objects to communicate with one another. These includeI/O streams for stream based communications and topic basedpublish/subscribe for data point based communications. The I/O Streammanager handles all I/O stream based connections and thePublish/Subscribe Manager handles all data point based connections.SES-DP input/output stream objects provide a convenient FIFO based bytestream implementation that can be leveraged to allow distributed processobjects to pipe data between one another. The SES-DP server provides apool of physical stream objects that can be leveraged by any userdistributed process. This pool includes the standard I/O stream sharedmemory objects that are included with the base SES-DP server by defaultand can optionally include user specific I/O stream objects that can becreated as plug-in modules using the SES-DP I/O Stream plug-in SDK. Oncecreated, these stream plug-in modules are assigned a unique name andadded to the SES-DP server using the System Root Process' exportedstream management command set. The I/O Stream Manager is responsible forassigning any of the available physical I/O stream objects to therequesting distributed process objects during process initialization.This is accomplished by setting the process specific initializationarguments that are present for each required distributed process streamto the name of the physical system stream. Users add I/O stream inputand output interface objects to their distributed process objects byutilizing the powerful SES-DP code generation framework. This isaccomplished by simply adding a line to the user distributed process XMLfile for each required input or output stream object and executing thecode generator. The code generator then automatically generatesinterface code within the user distributed process C++ files for eachrequired stream. Initialization arguments that assign the distributedprocess' stream interface objects to any of the available physicalSES-DP streams are automatically added to the distributed process by thecode generator. These arguments are then utilized during distributedprocess object initialization to assign a unique physical input oroutput stream to each of the distributed process stream interfaceobjects. Publish/Subscribe Data Based Communications by the SES-DPframework allows distributed process objects to communicate with oneanother using an extensible transport specific publish subscribeinfrastructure. As the names imply, publishers are responsible forwriting process specific topic data values and subscribers areresponsible for reading the published external values. Users can takeadvantage of the SES provided publish subscribe plug-ins or extend thebase publish subscribe implementation to create their own hardwarespecific publish/subscribe plugins using the SES-DP publish/subscribeSDK. All SES-DP publication and subscription objects use a canonicalnaming convention which includes the transport implementation in thepath. The SES-DP publish/subscribe transfer interface is topic centric.This means that data is transferred from the publisher to thesubscribers on a topic basis. A topic is defined as a collection of 1 ton data elements that is assigned a unique name on the publisher. Dataelements contained within a publication topic can be any of the typeslisted in Table 2-1. This includes Booleans, signed and unsignedintegers, floating point numbers and strings. In addition, numeric dataelement types may contain one or more elements.

TABLE 1 Standard Property Types Publication Data Element Types CommentBool The publication data element is a Boolean value or array Int8 Thepublication data element is a signed 8-bit integer value or array Int16The publication data element is a signed 16-bit integer value or arrayInt32 The publication data element is a signed 32-bit integer value orarray Int64 The publication data element is a signed 64-bit integervalue or array UInt8 The publication data element is an unsigned 8-bitinteger value or array UInt16 The publication data element is anunsigned 16-bit integer value or array UInt32 The publication dataelement is an unsigned 32-bit integer value or array Float Thepublication data element is a single-precision floating point value orarray Double The publication data element is a double-precision floatingpoint value or array String The publication data element is a string.

Each distributed process may contain zero or more data publicationtopics along with zero or more subscription topics. Both the publicationtopics and the subscription topics must be assigned a unique name withinthe user distributed process. Subscription topics from one distributedprocess are connected to publication topics from another distributedprocess at process instantiation time. This connection is handled by thePublish/Subscribe data manager and there is no instantiation orderdependency between the publisher and subscriber. This allows distributedprocess A to publish data that is subscribed to by an externaldistributed process B that is in turn publishing data that is subscribedto by distributed process A. When a distributed process subscription iscoupled to a publication from a separate distributed process, thePublish/Subscribe data manager ensures that the defined subscription iscompatible with the publication. The only requirement here is that alldata elements defined in the subscription topic exist within thepublication topic. This means that the contents of subscription topicscan be subsets of the contents of publication topics.

Once a publication topic has been defined, users can write thepublication topic data to the subscribers of the topic using the topicspecific SES publication object's PublishData method. Subscriber objectswithin the receiving distributed process object will see the new topicdata after the next topic specific subscription object's UpdateDatamethod is called.

The SES-DP code generator handles the generation of all of the topicspecific registration code and all of the publication and subscriptionspecific configuration code. Users simply define the names, types, andarray sizes of the data elements that are contained within each of thedesired publication and description topics using the schema base SESdistributed process XML configuration file and the code generator willgenerate all of the required C++ code automatically. The user then candecide where in their real-time processing code or command handling codethat they wish to invoke the publication operation for theirpublications or the subscription update operation on theirsubscriptions.

The SES-DP framework provides a collection of built in or user specificserver registered physical time source objects that can be coupled tothe time interface contained within any user distributed process atinstantiation time. Once a distributed process is coupled to a timesource object, the time interface objects can be used to synchronize thedistributed process object's processing to external time sources,physical hardware events, or any other distributed processing objects.If a distributed processing object's execution model type is framebased, the time interface object is used to control the object'sreal-time frame processing rate. With this configuration, thedistributed process' frame based processing code will automatically beadvanced each time the time interface object advances. This advancementmay either be at the physical time interface frequency or at a derivedfrequency relative to the physical time source frequency as determinedby the configuration of the distributed process' time interface object.When hardware interrupt based hard-real-time time sources are utilized,frame based distributed processing code can be directly advanced eachtime the interrupt fires. When a user distributed process object iscoupled to one of the available SES-DP time source objects, the usermust specify the desired derived frequency and offset that the userprocess will run at. The derived frequency value is specified in Hz andmust equal the parent time source frequency divided by a positiveinteger. This allows the distributed process to operate at speeds equalto the parent time source or at any natural divided value. The offsetvalue specified at initialization time is used to add a phase offsetinto the distributed process' interface clock. This value is in terms ofparent time source ticks and is only meaningful if the derived frequencyis less than the parent clock hardware frequency. The phase offset isalways defaulted to a value of zero if not set. If it is set, it must beless than the parent clock frequency divided by the derived frequency.The Time Interface plug-in repository contains all of the time sourceobjects that are loaded on the SES-DP server. This repository containsthe default SES-DP framework provided time source objects as well as anyuser specific plug-in time interface objects that have been createdusing the SES-DP time interface plug-in SDK. Once a user specific timesource plug-in has been built, the plug-in module must be loaded intothe SES-DP's time source plug-in repository. This is typically handledusing the SES-DP's resident FTP server.

The SES-DP framework supports both user specific plug-in and built intime source objects. The SES-DP framework ships with numerous generalpurpose time sources that can be used right out of the box to drive userspecific distributed process objects. These include the Internal SystemClock time source, the faster than real-time NRT time source, the SESNTSC or PAL video broadcast synchronization time source, and the SESexternal hardware event time source among numerous other SES developedplug-in based time sources.

The SES-DP framework's internal system clock time source allows the userto synchronize distributed process objects running on the same machineacross multiple CPU cores. This time source utilizes the SES-RtLib OSabstracted time source objects to drive the distributed process objectstime interface objects relative to the system's internal wall clock.Users simply specify the desired frequency of operation for each of theinternal system clock time source when the time source is created andadded to the SES-DP server using the SES-DP server specific time sourcecommands.

The SES-DP framework's faster than real-time NRT time source allows theuser to run the coupled distributed process code as fast as possiblewhile maintaining the specified synchronization relationships betweenall of the distributed processes that are coupled to the time source.Users can utilize this time source for computationally intensivedistributed simulation tasks where the minimization of the time tocomplete the simulation run is more important than running timesynchronous to a hardware clock source. One of the key benefits of theSES-DP framework is that users can then simply reconfigure the system torun the same simulation with one of the supported real-time time sourceswhen real-time hardware clock synchronization is desired. As with theInternal System Clock Time Source, user simply specify the desiredfrequency of operation for the faster than real-time time sourcealthough in this case, the frequency is used for synchronization andprocess execution rate purposes only.

Each SES-DP Server node utilizes an OS specific FTP server. The FTPserver is responsible for transferring plug-ins modules to the SES-DPserver. This includes user distributed process plug-ins, time interfaceplug-ins, and user specific stream plug-ins. Once a plug-in has beenloaded into the appropriate plug-in repository, the SES-DP server canthen be commanded to load and run the plug-in specific code on theserver. When the user has completed the desired operations with theplug-in module, the SES-DP server can then be commanded to unload themodule.

SES Distributed Process Objects (DPOs) are plug-in based user codemodules that can be dynamically loaded, configured, commanded, andunloaded on any active SES-DP server node that is resident on the user'snetwork. These plug-in modules are operating system independent andsupport real-time operations. Each DPO contains a command and eventinterface 302, a user specific processing engine 304, a timesynchronization interface 306, data communication interfaces 308, andsupport for external hardware control 310 as illustrated in FIG. 3.

All user developed DPOs are built from a common codebase that can becross compiled and linked to run on any of the SES-DP environmentsupported operating systems. This includes Windows, Interval Zero-PharLap ETS, RTOS32, Linux, and Solaris. The SES-DP Framework provides anadvanced DPO code generation/modification utility that allows users torapidly generate or modify their DPO specific C++ code and OS specificproject/makefiles by simply filling out a schema based XML,configuration file. This allows the user to focus his or her efforts onsolving the problem at hand without getting bogged down in frameworkoverhead issues. For more information on this topic, refer to section 4of Exhibit B. DPOs support hard-real-time processing applications andcan literally be written to support any user application. They providethe following features to the user: • Supports complete command andcontrol operations across a standard network • Supports user specificnetwork based commands • Supports user specific event notification •Supports hard-real-time processing operation within the user processingsection • Supports synchronization to internal or external time sources• Supports the auto-generation of DPO C++ code using the SES-DP codegeneration tool suite • Supports the auto discovery of user specific DPOcommand and control interfaces to all connecting client applications •Supports deployment on multiple operating systems without DPO codemodification • Supports Stream based I/O communications to and fromexternal DPOs connected to the system • Supports topic basedpublish/subscribe data communications between multiple DPOs • Supportsthe direct interfacing with system analog and digital hardware(including the direct programming of FPGA devices). All distributedprocess objects utilize the state transition diagram illustrated in FIG.5. After a distributed process object has been loaded on an activeSES-DP server, it must be transitioned to the Initialized state 502before it will accept a Start command 552 and transition into theRunning state 504. Once any distributed process object is in the Runningstate 504, its processing can be paused by issuing the Pause command554. From the Paused state 506, the distributed process' processing canbe resumed by issuing the Continue command 556. A distribute process canbe stopped from either the Running 504 or the Paused state 506 byissuing the Stop command 558. This transitions the distributed processback into the Loaded state 508 where it can either be re-initialized 560or unloaded 562 from the server. An Unload command 562 transitions tothe Unloaded state 510, from which a Load command 564 can cause atransition back to the Loaded State 508.

FIG. 4 is a flow diagram illustrating steps involved in an exemplaryembodiment. The steps illustrate a method for providing a distributedprocessing framework 400. Initially, the process begins by building aserver process plug-in by invoking a code generation module to generaterequired boilerplate and cross-platform code 410. Then the processincludes commencing a server process by loading plug-in code and givingit a thread of control 420. In addition, the process includes clientmachines discovering the existence of a plug-in code being executed 430.Further, the process includes one or more client applications running ona client server at least issuing commands to the plug-in code,monitoring the events of the plug-in code, update the properties of theplug-in code without information regarding the plug-in interface 440.

It will be appreciated by persons skilled in the art that the presentinvention is not limited by what has been particularly shown anddescribed herein above. Rather the scope of the invention is defined bythe claims that follow.

What is claimed is:
 1. A method for providing a distributed processingframework comprising the actions of: building a server process plug-inby (a) accessing a description file that specifies one or more of aplurality of commands, a plurality of properties, a plurality of eventsand a plurality of streams and (b) invoking a code generation module togenerate a required boilerplate and an operating system independentcross-platform coding; commencing a server process by loading the serverprocess plug-in and giving the server process plug-in a thread ofcontrol; the server process publishing a subscriber interface that canbe discovered and invoked by any of a plurality of client applicationsrunning on any of a plurality of client machines; and one or more clientapplications invoking functionality of the server process by issuingcommands to the server process in accordance with the publishedsubscriber interface; whereby the server process plug-in can be modifiedand updated, thereby changing functionality without modifying the one ormore client applications.
 2. The method of claim 1, wherein upon loadingthe server process plug-in, the server process enters a loaded state andupon receiving an initialize command from a client application, theserver process transitions to an initialized state.
 3. The method ofclaim 2, wherein when the server process is in an initialized state, theserver process transitions to a running state upon receiving a startcommand from a client application.
 4. The method of claim 3, whereinwhen the server process is in the running state, the server processpauses upon receiving a pause command from a client application.
 5. Themethod of claim 4, wherein the server process transitions to the loadedstate upon receiving a stop command from a client application.
 6. Themethod of claim 1, wherein a client application can perform variousoperations by sending commands to a first server process running on afirst server and a second server process running on a second server. 7.The method of claim 1, wherein the one or more client applications arewritten in a high-level scripting language.
 8. The method of claim 1,further comprising the actions of: receiving listener registrations fromone or more of the plurality of client applications for a specificserver process event; the server process triggering the specific serverprocess event; and automatically transmitting the properties of thetriggered specific server process event to the client applications thatprovided listener registrations for the specific server process event.